Method of manufacturing tubular frame structures



Jan. 24, 1950 H. L. KRAEFT ETAL 2,495,333

METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. -18, 1945 l2 Sheets-Sheet l LNVENTORS. HERMAN L. KRAEFT LEONARD J. WALTERS RUDOLPH F SKERL m RAM/ H. L. KRAEFT ET AL Jan. 24, 1950 METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES l2 shetssheet 2 Original Filed Aug. 18, 1945 RS. HERMAN L. KRAE'FT RUDOLPH F- SKERL BYGZGQW, 61?) LEONARD J. WALTERS Jan. 24, 1950 H. 1.. KRAEFT ETAL 2,495,333

METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES,

l2 Sheets-Sheet 3 Original Filed 'A'Iig. 18, 1945 NNM . Ava 4$ wm mum mam w .H a w n u a fia fia wmkfi oh w M f v s a? wa vv k =m r-r Il 9 MN THM kqmv nhmm h NR. 7 I HUM A 8 m hm QR awn I .m an m & n ,H. .F mink J my MLJ v 8% m H M4 Even a 6mm 8 m mu 0 hm RMD mmm. m mum wumm Jan. 24, 1950 1-3. L. KRAEFT ETAL v 2,495,333 METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. 18, 1945 12 Sheets-Sheet 4 M mLmv 3 TR 3 ELE mA K MR S K Q q 3% Q TH mwm swH MMM ,I9A7T/IIVIVMI fivl illlllr n 0 D 9 n 1 1 Ill: U 1 EH HLRY t B Jan. 24, 1950 H. L. KRAEFT ETAL METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES l sh ets-sheet 5 Original Filed Aug. 18, 1945 Jan. 24, 1950 H. L. KRAEYIFT ET -AL 2,495,333

METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. 18, 1945 12 Sheets-Sheet 6 29 A J 5 I ..'s I 5g JIO F :E 1 F l INVENTORS. HERMAN L.KRAEFT F 2 LEON/RED J. wag-I 5:

RUDOL H F. H

Jan. 24, 1950 H. L. KRAEFT ETAL 2,495,333

METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. 18, 1945 12 Sheets-Sheet 7 mmvrbns HERMAN L. KRAEFT LEONARD J. mums: RUDOLPH r; .SKERL Jan. 24, 1950 H 1.. KRAEZFT EM 7 2,495,333

I METHODv OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. 18, 1945 12 Sheets-Sheet 8 170 I ll I I 2 206 I,

I u T J] 261 ay g if :1 Z 26 H 38o 5 WWW 22:5 378 64 o\ a I 2 T266 2 a 3 165 E Jan. 24, 1950 H. 1.. KRAEFT .ETAL 2,495,333

METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed Aug. ,18 1945 12 Sheets-Sheet 9 \1 O Om M m) nwu 0Q ST I Wm 6 :Lfln VW/WVT M 1 NW! I D. 3 1 n -IIU... INA. QQQQMN HK S NNN p. F m .nww ins mLJr. n ivw fr 0 Q at" 1 1 S L, 3 mr. 9/ mu m .mm mm l I 4 L mam xnw flgm mw v fi y ma j a MM G w .l mu E 5Q W mm $3 I l 03 o N Jan. 24, 1950 H. L. KRAEFT ETAL METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Original Filed.Aug. 18, 1945 12 Sheet-Sheet 1o I 323 W m on \1 1 II- I s: i?

t 225 i @E mum/10x5 HER MAN L. KRAEFT LEONARD J. WALTERS RUDOLPH n SKERL METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES 12. Sheets-Sheet 11 Original Filed Aug; 18, 1945 a E KMS 2, N JD Wm a RWM WO u 7 mm HLR 9 Jan. 24, 1950 H. L. KRAEFT ETAL 2,495,333

METHOD OF MANUFACTURIyG TUBULAR FRAME STRUCTURES Original Filed Aug. 18, 1945 12' Sheets-Sheet 12 /N|/EA/7'0/5 HERMAN L. KRAE FT LEONARD u. WALTERS: RUDOLPH E SKERL Patented Jan. 24, 1950 METHOD OF MANUFACTURING TUBULAR FRAME STRUCTURES Herman L. Kraeft, Cleveland Heights, Leonard J. Walters, Shaker Heights, and Rudolph F. Skerl, Euclid, Ohio, assignors to The Murray- Ohio Manufacturing Company,

Cleveland,

Ohio, a corporation of Ohio Original application August 18, 1945, Serial No. 611.286. Divided and this application May 31, 1946, Serial No. 673,690

8 Claims.

This invention is directed to the manufacture of tubular frame structures such as velocipede frames and the particular disclosure herein set forth illustrates a novel method and an apparatus adapted to the fulfilling of several steps of the method of manufacturing bicycle frames. The present application is a division of our application Serial Number 611, 286, filed August 18, 1945.

In a prior Kraeft and Powers application Serial No. 513,163, now Patent No. 2,435,448, a bicycle frame is disclosed having such structural characteristics as to make feasible the pre-assembling of all of the elements or parts of the frame whereby a simultaneous copper brazing of all of the frame parts, including reinforcements, could be effected in a highly advantageous manner by heating the entire frame to a copper brazing temperature in a non-oxidizing environment. This resulted in the production of a strong frame of such external neatness and cleannes's as to obviate the labor of trimming, grinding and filing of fiashings or drippings unavoidably incurred in welding and brazing methods heretofore practiced in the velocipede frame manufacturing art. In said application the preconditioning of the preassembled frame joints to withstand the expansion of the frame parts when raised to a copper brazing temperature of from 2025 to 2080 F. without a resulting disruption of accurate relationship of the parts at the joints comprised a salient feature of the disclosed method.

Generally the method comprised effecting a close fitting of the parts at the joints and the preliminary maintenance of the joints by a temporary locking of the joined tubes through the use of spot welds or the like that would hold the assembled relationship of the inserted ends of the smaller tubes which had been close fitted into openings formed in the larger tubes. While the ultimate purpose was fulfilled, the joint spotting in some instances was awkward and uncertain in that occasionally spot weld failures would develop during the high temperature period of the brazing with a resulting slippage at one or more of the joints. Hence a certain percentage of the completed frames would have to be discarded since such a completed frame could not be salvaged.

The general object of the present invention is to simplify further and to improve the mode of assembly and the temporary bonding of the joints of the assembly whereby the entire frame assembly will remain so thoroughly locked that when the entire frame is heated to approximately Lil 2 2000 F., practically no subsequent straightening of the frame elements is required.

Another object is to provide a pressure mode of joint forming preparatory to a copper brazing operation which eliminates the general need of a tube looking or a securing medium at each joint to maintain the inter-relationship of the joined tube members when expansion thereof takes place during the brazing operation.

A further object of the present invention is the provision of a novel method of simultaneously effecting a pressure assembly of several subassemblies comprising a tubular velocipede frame in such manner as to avoid the creation of troublesome localized stresses in the tubular elements which would cause warping in a subsequent simultaneous brazing operation.

A further object of the present invention is to provide a mode of effecting a press fitted preassembly of the various tubular elements comprising a bicycle frame whereby the over-all accuracy of the pre-assembly will be maintained without the use of heat consuming fixtures during a general brazing operation in which the entire frame is heated to temperatures of from 2025 to 2080 F. while standing in an upright position.

The present invention contemplates the use of an order of assembly of the various elements and parts comprising the velocipede frame whereby very substantial pressures can be utilized to effect very tight press fits of from .005 to .015. We have determined that severe press fits will eliminate all danger of a spreading or creeping of the frame parts relative to each other when heated throughout during a brazing temperature of over 2000" F. and without interfering with the capillary migration of the liquid copper. Th pressures required to force the smaller tube ends into the openings formed in the Walls of the larger tubular elements are quite substantial and, due to the fact that most of the reach bars comprising the frame are curvilinear in shape, the mode of supporting and conditioning the elements to receive such press fitting forces and the mode of force application is such that proper alignment of the interfitting press fitted parts can be maintained during this operation. The operation of internal stresses and strains which would become manifest in distortions and bad joints when released during the overall high temperature brazing operation is avoided.

Our method, which is here disclosed as applied to making bicycle frames, accordingly comprises the formation of four sub-assemblies of the e1ements which consist of the bicycle frame, to-wit;

the double walled head or front fork bearing housing tube having two non-parallel openings formed therein a nd into .which openingsends of curved upper and lowerreach bars havebeen press fitted; the center or seat post mast tube assembly formed of a double walled hanger housing tube having four openings of different diameters formed in the double wall thereof with the center tubelowenend press fitted into one of the openings and a branched seat post cluster member; press fitting,

upon the outer surface of the center; mast tube in a desired position, (dependentupon whether a girls or boys bicycle frame is toJmproduced); and tworear fork sub-assemblies, each consisting of an upper rear fork tubular member. and a lower rear fork tubular member; ofcurvilinearshape with one end of each tube flattened to be press fitted or otherwise secured to lugs orbranches formed on rear axle plates or yokes. Thevarious smaller tubes have reinforcing inserts assembled within theiend.- portions thereof: In the drawings we have shown apparatus for .efiectingthe. various steps of theprocess-herein claimed, the apparatus .per se .havingbeenclaimed in said application Serial No.. 611,286. 1 In saidannexed drawingsz Fig. 1 is .a diagrammatic representation. of four pie-assemblies -.'comprising a boys typebicycle frame;

Fig. 2 is a diagrammatic representation of four pre-assemblies.-comprising a girls type bicycle frame;

Fig. 3.is a top. plan view of a machineforeifecting -the.fina1. assembly of the four preeassemblies comprising the bicycle frames andas adapted to .-.efiecting suchfinalassemblies of .both boys and girls type of bicycle frames;

ig. 4. is apartial plan View, onanenlarged -scale,.of. themechanism shown in Fig. 3 to. emphasize the mechanismfor clamping, guiding-and press fitting. the-two pairs of vrearframe assem- '.:blies, each consistin'gpf an upper fork. tube, a

.lowerforktubeand rearaxle plate, to. the center mast pre-assembly; Fig. 5'. is a partial side. elevation of themechanism shown in Fig. l;

Fig. 6 is acrossesectionalelevation taken substantially alongtheline 66 of Fig. 4 through a Sliding clamp .fixture which carries the two rear axle plates.andattachedtubes in properly spaced relation;

-.Fig. 'l is aside elevationof the final assembly machine shown in Fig. 3;

Fig. 8 is a. cross-sectional elevation taken through the head tubeor front bearing housing tube gauging and clampingmechanism and substantially along the line 8 -.-3 ofFig. 3;

.. .Fig. 9. is across-sectional. elevation taken substantially along. theline 9-9 of Fig. 3 through the center.mast assembly gauging.and clamping bing means for locking the upper front reach bar to the center mast clusterby a metal indenting .operationandas adapted to such lockin for both boys and girlsv type frame;

4 Fig. 14 is an enlarged cross-sectional elevation taken substantially along the line I l-I4 of Fig.

Fig. 15 is an elevationahyiewsimilar to Fig. 14

on a smaller scale;

Fig. 16 is a side elevational view of a sliding cam mechanism for effecting actuation of the nibbing, mechanism shown in Figs. 13, 14 and 15;

. Fig. 17 is a cross-sectional elevation of the upper front reach bar or tube gauging and actuating. meansand taken substantially along the line Fig. 18 is a fragmentary cross-sectional view taken substantially along the line l8l 8 of Fig. 4

, Fig.. 19 is a fragmentary cross-sectional view taken substantially along the line l9-l 9 of Fig. 4; Fig. 20 isanenlarged plan view of the seat post or ce nter mast cluster clamping means and tubularguiding means for guiding the ends of the upper rear fork tubes and the rear ends of the upper reach baritubes during the-press fitting of the same to the. center. mast cluster-assembly Fig. 20A is aside elevation; of the'center. mast clamping mechanism 1 as viewed. from; .the.- right of Fig. 20;

Fig. 203 is an elevation of the rear. upper..- fork .tube guiding meansas viewed-from the'position indicated by the line"20B,2iiB,in;Figi20;

Fig. 200 is aside elevationalview-ofthe means shown in Fig. 203 as a.viewed.,from..the -.-left.=of Fig. 20;

Fig. 20D is. an elevational view; of .the girls-fytype .cluster clamping zandstube guiding means. as viewed. from a positiondndicated, by the: line 20D. 2UD in Fig. 3;

- Fig. 21 is a planviewoftheyhangenhousing gauging and clamping means shown inFig. 13. but enlarged for the purpose of disclosure;

=.Fig. 22 is .anelevational1view of a part Ofuthfi mechanism shown in Fig. :21. and .as viewed. from the direction indicated .by the line. 22+22..in Fig. 21;

Fig. 23 is a crossesectional view of. thehanger housing gauging andclamping meanstaken substantially along... the irregular line 33- 23 of Fig. 21;

. Figs. .2eland 25 are enlarged elevational yiews of the hanger housingclamping mechanism to show the means. for; effecting the operation thereof;

Fig. 26 is atop plan. view of the mechanism shown in Fig; 3 to-illustrate the locationbf the hydraulic means for operating the .various. fixtures comprisingthe assembling machine;

v Fig. 27 is a side elevational-.view.of..the.hy-

draulic mechanism indicated in.Fig=. 26;

l Fig....28 is a .crossesectional.elevation.of the machine taken substantially. alongthe line-28:48 of Fig. 27 to illustrate a knockout mechanismfor extracting or elevatingthe.c ompletely .assemhled frame out of,.the machi ne and Fig. 29 is a fra mentary. end yiew of the knockout mechanism: sho;wn in Fig. 28.

Figs. 1 and .2 comprise 'moreor less diagrammatic representations of the pre assemblies comprising a boys and a girls type bicyele f ame. The manner of press fitting the elements of these sub-assemblies and the apparatus for effecting the same isdisclosed in said application s rial 70 No. 611,286? The front sub-assembly comprises front fork bearing tube 49, an upper reach'jbar EZ and lower reach bar- 53press fitted into openings in the large tube 49. The rear sub-assemblies comprise an upper rear fork tube- I 3| and a lower rear fork tube 4 L30 secured and =-abutting to' fiat axle plate I32 press fitting on lugs [32a and l32b, there being a right and left-hand wishbone-like pre-assembly. The center mast comprises a separate sub-assembly with the elements press fitted together. This center mast assembly comprises a hanger housing tube I60, a main or center mast tube IBI, a four-branch cluster or tube-joining means I82 and a seat post supporting tube I83, as shown in Fig. 16, for the boys frame. In the girls frame, in lieu of th cluster I62, there are two clusters I64 and I85. These various hollow members are press fitted by any suitable means to accurately form the tubular center mast pre-assembly structure illustrated.

The branched cluster I62 (see Fig. 1) may be press fitted along the mast tube to the desired position by a slidable clamping mechanism and the respective mechanisms may be effectiv to produce the center mast sub-assembly with the center line of the hanger housing properly disposed relative to the center lines of the branches of the cluster member. In the girls type the two branch members I54 and I65 are similarly fitted.

The final assembly of the sub-assemblies above described is effected by fixedly supporting the center mast assembly through the use of a gauging means extending into both ends of the hanger housing and with associated clamping means 7 and, further, by the use of clamping means which firmly engages the cluster portions of the center mast assembly. The front sub-assembly and the two rear sub-assemblies are then positioned with the free ends of the smaller tubular elements thereof substantially in alignment with the openings in the branches of the cluster member and the openings in the tubular wall of the hanger housing member. While maintaining this relationship, compression forces are applied to the head end of the front assembly and the rear ends or plates of the two rear fork assemblies so that the free ends of the smaller tubes of the respective assemblies are shifted toward each other and into the openings in the cluster and hanger housing. This operation is effected by applying forces in a general longitudinal direction relative to the smaller tubes of these assemblies in substantially precision relation to the respective openings into which they are to be press fitted. Means are provided for gauging the longitudinal movement of the ends of the smaller tubes after entrance thereof into the openings of the center mast assembly so that a proper relation of the smaller tube ends to the front housing, to the hanger housing, to the seat post cluster and to the rear axle plates may always be obtained regardless of variations in the resistance encountered at one tubular joining point relative to another. The result is an overall accuracy of the disposition of the hanger housing relative to the front housing or head and the rear axle plates without any undue localized strain of any of the tubular members and jointures comprising the preassembled frame. A final locking is effected between one or more of the front reach bar ends and the center mast cluster in addition to the press fitted connection therebetween. Mechanism for carrying out the above outlined method of final assembly comprises the hydraulically operated final assembling machine shown in Figs. 3-29 inclusive, of the drawings.

The final assembly machine for press fitting these four preliminary sub-assemblies together comprises a front gauging, clamping and guiding mechanism for the front sub-assembly, a

gauging, guiding and clamping mechanism for the two rear sub-assemblies, and a gauging and clamping mechanism for rigidly positioning and holding the center mast pro-assembly. Hydraulic means is provided for effectively press fitting the six free ends of the tubular members, comprising the front and rear assemblies, into openings in the center mast assembly and means for separating the completely assembled frame from the mechanism after the frame has been press fitted and locked together, also is provided. The order of description of these various mechanisms will be followed hereinafter generally as outlined above. Associated with the respective slide mechanisms are cam operated tube stabilizers'for preventing buckling or distortion of the curved tubes when longitudinal pressures are 'exerted thereon by the hydraulic means.

I The front mechanism for receiving, gauging, clamping and shifting the front sub-assembly toward the fixed center mast assembly to press fit these two assemblies together is illustrated in Figs. 3, 7, 8, 10, l1, l2 and 17 of the drawings. This mechanism comprises slide structures operatively supported upon a heavy plate I10, forming the table or bed of the machine, and a supporting framework for the table is indicated generally in the drawings. The front slide mechanism supports two oppositely disposed pneumatic or hydraulic piston cylinder mechanisms Ill and I12 which operate oppositely disposed gauging plugs that fit into the open ends of the head or front housing tube 49. The slide mechanism, including the pneumatic or hydraulic cylinders Ill and I12 is shifted or operated as a unit by a hydraulic cylinder mechanism I14 and the controls therefor may be conveniently located on the top of bed I10. In Figs. 8, 10,

11 and 12 the slide mechanism is shown as comprising a main slide structure I15, a base plate I16 supported by the table I10, slideways I11 and a carriage plate I18 secured to the slide structure.

I The carriage plate is reinforced to obtain stiffness by two spaced apart truss members I19 and I80, to which the hydraulic cylinders Ill and I12 are attached and disposed therebetween. Carriage plate I18 is provided with a further slideway structure comprising slide gibs I8I secured to the table I10 of the machine and which slidably engage stabilizer slide members I82 secured to the under side of plate I18 in operative relation to the members I8I. The hydraulic piston cylinder mechanism I14 has a connecting rod I14a thereof connected to the slide structure I15 by a bracket I83 and a pin I84 extending through the bracket and a yoke-formed end of the piston rod I14a.

'A third slide structure is' provided comprising the slide member I98 placed above the plate of the table and operating upon blocks I99, which also form a support for the hydraulic cylinder mechanism I14 disposed therebetween. Gibs 200 are secured to the members I99 to complete the slideway structure. The forwardend of the slide I98 comprises an integral bracket formation I98a which abuts and is secured to the truss member I80. The central region of the truss members is cut away, as shown in Fig. 11, to afford visibility and access to the operating position of a cradle member I88 secured to the carriage plate I18 and which is channeled to receive the front housing 49 and attached tubes, 5 I--53. The channel formation will vary for a boys type or girls type frame.

Retractable gauging plugs I89 and I90 are carerases-ass a; ried by slide members I 9;i:;.and-::l 92;; r s ect vely.

and. wh h opera e:- in, slideway .3" a d?! 94:.disposedatopposite..ends: of the-cradlememb n 1-8 -:The shapes of thegaceine-p1ues 31 9 rand: l 90 ....are suchast-o engaeethe-ends of...thezhe d:tu v ,;69,to.;;,center it andalso,togservegasestopsvfor limitingnthe inwardgmovementflof ;the;:,ends;;of their-each bar tu es-.52:andxssuwhen pressu e is 1 exerted generally-lon itud na ;unonihe. ubes. gslidememh rs E91 and-d92;x arrx nethese aai ins: -.-piues. .imarlbe, con ect d ozzth ;.hydr ulic :conne tine m hanismeIILan HIZ ne 9 1 venient means,-, suchaspivotal pin;conneg ons r-! 94;l 95 respectively.q-In Fig. lQ'gthe adaptation of: the mechanism described -for;both;bQySfla-nd girls typeframe ofiassembly is indicated;by;.the L dot; and :dashi lines, and reference-.;.-numer;als 52 and 53. It will beseen that themechanism-above ,;-,described comprises in effect four slide structures which: afford very substantial operative. stability :tothe mechanism or v fixture for clamping, gauging and shifting. the front -s ubeassembly of the frame linto press fitting relation to "the center mast; assembly.

Associated with the slide mechanism described. and immediately. adjacent tube 52? boysi ftypel; is a tube. guiding and stabilizingmeans disposed to react-longitudinally along thecurved upper reach ban-52 .whereby ,the reach bar. will, b e prevented from being distorted under. the "press ,fit-. ting forces required to efiect the pressfitting'as -.sem-bly. This mechanism is;-shownin .Figs-. 4

and l? and comprises a shiftable shoe member 285, having. a vertically extending surface-to tangentially conform substantially to the curved. shape. oi the upper reach; barp52. :'Ihis,,shoe --member iscarried byan arm orbracketzflfi securedto the forward trussmember I19 fl he ..-,bracl-:et 2536 is provided with a .slide-dormation :Zfifiw which is supported by abase.. block;..201 secured-to thetable H3 ofthemachine andthe slide reacts against a slide gib. zilfiucarriedby the block 291. A fixedblock=42ll9serves tos lpport ,th under-side ofthe reach bartube,52.. .The .top region of the tube is-stabilizedby a.;r etr,actable 7 bearing member 12H carried-by a..slide;bar.2l I, .shiftable into and outofoperative. 1: osition by amanually operated leve1t.2l2. Thelevcr. -2l2 is pivot-ally mountedon a pin 2l3..carried by a bracket structurezi l secured;.to-the. .block struc--. .tureQG'i-JBQ. Thus, as the frontsuh-assembly is shifted toward the. center-.mastassembly and under compressive stresses, .tube.52,. is supported along its: path oi,movementamngthree ,lines .:,,about 90?.apart. When it, is desiredtosremove the completed frame from the mach-ine the upper bearing or thrust member 2| can be retracted out of the Way, oioperationm .theleveiHZ l2 in an obvious manner.

.The means for gauging. the centerrmastoaa, sembly in themachine comprises a pneumatically or hydraulically. operated .gauging, pl ug,...2l9 adaptedto .fit into. the upper. open end of... the -housing tube; .l.6i and .cooperatewith asecond gauging plug .22 5 secured .to. the table. Gauging -means are associated Withthehanger housing clamping means-for.- guiding the free-ends of: the ,7 two .lowerrear fork;.-,tubes,,toeopenings in the hanger housing. and :also. for .guiding the lower free-end of the frontreach bar 531; to. enema-c- --sponding openingformed in the hangeryhousing. This center mast: holding-.mechanism. alsoiineludes aga-uging and clamping means,for-...elamping the cluster structure I62 of thecfignter mast -,assembly', in :the teaser. ofv a boys- :bicycle frame,

.eandr: the 3 .cluster. structures i 64.; and i 6 5;: intrthe case, :of a;gir1si type frame. Associateduwith e upperv-cluster, clampin means is aremovable spacing ;barin sertablebetween -and. retractable from ayposition-between theetwo upper-rearfork ;'--members. A. .similar mechanism acts between 1 the-two lower rearfcrk tubes. All of these mechanisms aresuch asto be swung or. shifted clear of the'complcted framefor the readyextraction m of .the frame from. the machine when the-press fitted assembly has been completed. Themech- .oanismhfoi .gauging-.,andclamping .the .hanger housing. is best shown in-Figs. 1', 9,21, 22,23,24

and 25.

;;, 7 With referenceto-Fig. 24, thebottom gauging plug. 2l5 is shown supportedrby a blockmember ;2 I Bi-securedtto a plate 2 l I supported :upon; ;the top;surface of the machine table. H0. The upper .gauging.-plug 5219 is mounted upon a. shiftable ,.,b1oc1 2zc. secured to a slide 22!...operated in a slideway structure-222 formed on a vertically.v extending bracket 223 secured to plate memberZ I I. The slide structure;22fi2'2 i and .theupper. auging plug .249, operatively. supported thereby, is

.;actuated by. a.pne.umatic. or hydraulic .pistoncylinder mechanism 225 through a link member .2226.pivotallyconnected bypin. 22.1 to the piston ,-.-1tod..228. .The linkNB operates a lever member .129. which is .pivotally supported at. 230 ,by. a

bracket member 23.! mounted .on .the upper part not the .slidebracket 223.. The inner end. of lever memberi29. ispivotally connected at 23l to.link member 232 which is pivotally connected atj233 ..to.,the. slide..blockf22%.. The cy1inder225ma'y .be

. attachedto, the side of the machine frame .in

trajctingor stripper pinsr ififl and the. manner of 7 operation thereof will be described hereinafter. Associated with the hanger housing gauging and clamping means is aguide, block 235 secured to the plate member 2|! which has achannel wiormed therein for thepurpose of guiding the j freeend of the lower reach bar153 into the'cor- ,respo'nding opening formed in the hanger housing t u be.'49.';"This channel formation is closedby a I padf235 mounted on or comprising a part of the 1id6 bk.,222. A similar guide block 238 isdis- ..-l :0S.ed,.0n the opposite side of the hangerhousing position, note Figs. 21,and. 23, and is provided .,..w.it h .a. channel shaped guideway to generally con- .form. to. theshape of the lower rear fork,.tubes (,5 -130. Ashapedpadliifl carriedby the. slideblock .o 2 2fl..serves..to close. the channel. -.A. retractable positioning and .gaugingbar-lw operates in. an ,iopeningnformedin-theblock 238 togauge the spacingbetween the forletube ends l30-when bewging. pressed .into? the hanger housing openings. The bar 240 may be operated manually. Pad.239, .-:..:a- 1s0 carried-by: slidemechanism 2-20, closes the channel in block .2 38. iThe baritll (see Fig. -22) ay; also. be ,operated i-by a link mechanism comprising alever member :2ti pivotallyimounted-at 246 on'a bracket 241 secured to mast slide bracket 223. Lever 245 is pivotally connected at 248 to a link member 249 pivotally connected at 250 at its opposite end to the slide formation 220. Upward movement of the slide 220 causes the link mechanism to be shifted to the dotted line position shown in Fig. 22, effecting retraction of the bar 240 from between the lower rear fork tubes I30.

The means for gauging the upper portion of the center mast assembly is best shown in Figs. 3, 4, 20, 20A, 20B and 20 C. Referring to Fig. 20,. a gauging block 260 is provided with gauging channels conforming in shape to the external surfaces of the cluster structure I62 for both boys and girls type of frame. This mechanism has associated therewith a nibbing means somewhat in the form of a center punch mechanism for indenting a branch wall of the cluster and the inserted end of the upper front reach bar tube, as will be more fully set forth. This nibbing mechanism is duplicated at a second center mast cluster position for the girls type of frame and a common actuating means is provided for operating both punches. A. second or intermediate cluster clamping means is provided on the machine for receiving and clamping the second cluster of the girls type of frame.

Again referring to Figs. 20, 20A and 203, it will be noted that the block 266 has associated therewith an adjustable clamping pad 26I carried on an arm 262 which is pivotally supported at 263 by a bracket 264 secured to a spacer block 265 sup ported by the table I10 of the machine. The arm260 is connected intermediate its ends to a link 266 pivoted at 261 to an over-center swinging lever member 268 pivotally connected at 269 to the bracket 264. This clamping means is swingable upwardly and outwardly away from the frame cluster so that the assembled frame may be readily removed from the machine and the disposition is such that the clamping pad 26I will clamp the cluster I62 firmly in the channel formation of the block 260. Associated with the cluster clamping mechanism just described are right and left-hand tube guiding means comprising channeled blocks for guiding the free ends of the two upper rear fork tubes I3I and the free end of the upper front reach bar tube 52 into the respective branches of the closure structure I62.

In Fig. 20B, block 213 is shown as being provided with a channel 214 shaped to receive and guide the upper rear fork tubes I3I to the two receiving branches of the cluster I62. This channel is closed at the top by a shiftable plate 215 bifurcated at one side and hinged at 216 to a lug 211 formed on the block 215. Opposite to the hinge structure 216211, as viewed in Fig. 20, is a swingable locking knob 218 in threaded engagement with a swingable stud 219 pivotally connected to the block 214 which swings into and out of a slot 286 formed in an end of the plate 215. Thus, the plate 215 can be swung about hinge 216 upwardly and outwardly to permit removal of the assembled frame.

Associated with the guide block 215 is a retractable space-r bar 282 (see Fig. 206), which is disposed to slide in an opening formed in the block 214 and have the tapered or wedge shaped inner end thereof extend between the ends of the two fork tube members I3I and thereby accurately determine the spacing therebetween at the time the tubes are being press fitted into their respective branches of the cluster structure I32. Bar 282 may be shifted inwardly and outwardly in any convenient manner, such as by a manually 10 operated lever 284 pivotally supported by a bracket 283, the end of the bar 282 being bifurcated to afford a pin connection between the bar 282 and the lever 284.

For guiding the free end of the upper front reach bar, a channel block 285 is provided, which channel is closed by swingable plate 286 after the manner of operation of the plate 215 for completing the guiding means for the upper front reach bar tube 52.

For the girls type frame a second mast cluster clamping means and a tube guiding means are provided, generally indicated by the reference numeral 360 in Fig. 3, for clamping the second cluster structure and upper front reach bar, and the construction thereof may be generally as above described with reference to the clamping member ZBI and front reach bar guiding means 285-486. The mechanism 300 comprises generally a channeled block 31H, hinged plate 302 and manual locking knob 363. Disposed forwardly of the center mast tube position is a cluster clamping member 3&4 which may be operated in the manner of the clamping member 26I. V

The mechanism for receiving, supporting and forcefully shifting the two rear fork assemblies comprises generally clamping means separately engaging each of the rear axle plates of the two rear sub-assemblies. These clamping -mechanisms are carried on a hydraulically shiftable slide mechanism. The slide mechanism carries tube supporting and guiding arms pivotally connected with the slide mechanism and controlled in their tube guiding movements by cam members fixed to the table of the machine. This mechanism is shown in Figs. 4, 5, 6, 18 and 19.

InFigs. 4 and 5 a main slide member 3l0 is shown as being operable in a slideway structure comprising a bottom plate 3 and slideway ibs 3I2 secured to the bed I10 by bolts 3I3. The forward end 3llla of the slide structure is narrowed to have a stabilizing slide formation operable in slideways or gibs 3I4 secured to the plate 3 and the machine table by bolts 350. The slide member 3IIJ carries clamping anvils or clamping block mechanism comprising an upper gauging and clamp plate 3I8 and. a lower gauging and clamp plate 3l9. The upper surfaces of these plates are contoured or recessed to conform generally to the edge contour of the rear axle plates I32. The upper plate M8 is supported in spaced relation to the lower plate are by a bracket structure comprising two spaced members 326. The upper surfaces of these clamp plates 3I8 and 3I9- are disposed in planes located substantially equidistantly above and below the common plane of the center lines of the center mast assembly and the tubes of the front subassembly when present in the machine. An upper locking or clamping member 32I is supported by an arm 322 in clamping relation to the upper plate I32 and is rockably carried on a bolt or stud member 323 supported by the clamping plate 3I8. The clamping lever 322 is operated by a cam member 325 fixed to a stud shaft 326 journalled in the bracket members 320. Also fixed to the stud shaft 326 is a manually operated lever 321 whereby when cam 325 is caused to wedge up against the under side of the clamping lever 322 an effective clamping of the rear axle plate and associated tubing by the clamping member 32I is obtained. A lower stud shaft 336 and manually operated lever 33E comprises a duplication of the upper clamping 5 means just described. Operation of a lower To operate the slide Sit a hydraulic piston-cylinder- -arrangement set is provided which may be secured-to the top of the' table bed HEB-of the machineand the piston rod 34! thereof is pivotally connected at 352 to a bracket 3&3 secured to and spanning the ends of the bracket members 32th Referring particularly to Figs. 4, 6, 18 and 19, it will be seen that means, carriedby the slide mechanism 3%, is provided for the supporting and the guiding of the two pairs of rear fork members-or tubes in additionto the clamping -T;

and gauging mechanism.- This tube guiding means compriseslevers 35il' and SM pivotally supported at sfizandlocated substan-tially' equidistantbetween the clam-ping surfacesoi the clamping-plates 3E8- 3l9.="- Leve-r'- members 35[l35lcarry guiding" at the sides of the" bracket'plates are by bracket members 354 and th upper-and lower fork tubes and determine the-outward spacing of-thetubes. These shoes is are carried 'byrockable' brackets 3.5"! and-358j respectivelyf-onpivot pins 359 carri d by the free ends of thelever members 353 35 i. Mounted upon -the lever members 356 359, between the outei'fre'e'endsthereoi'arecam rollers 35% and- 36F; respectively." These cam rollers ride upon cam-=members'"353 355; supported by bracket structures 385 secured to the table top 578 of the? n'iacl'iine: Spring membe to *maintain the lever 358 with the rollerfifiil in contact/with thecam at all times. A likespring" 31lmaintains rolleriifi i-=in contact with cam 364.-

r 3% is attached to "the-bracket structuresllfi and to the lever-35 3 It willbe seen that the mechanism just"described-is adaptable forthe reception, gauging, clamping and movement of the two rear fork assemblies, eachcomprising anupper and a lower rear fork member previously press fitted to a rear=axle plate. The shapes of the cams 363 and ii'fi are so arranged as to cause the shoe members--355j35i to firmly support the upper and l'ower spaced apart fork-tubes as the ends of thesetubes are being moved along and through the ch'annels formed in the guide-blocks 238, 213'so-that sidewise deflection of the tube mem--* hers is prevented duringthe press-fitting opera tiohmfthe'tube ends into the cluster structures and the/hanger housing openings of the center mast-cluster assembly.

It will be noted that the channels of the various-tube end guiding mechanisms are shaped to converge precisely to six respective socket openings of the rigidly held center mast assembly 1 and-that the tube ends regardless of their particular direction of movement by the slide movementsl must fol-low-the'center lines of the sockets or openings'during-the press fitting action.

In .Figs. 13, 14, 15 and 16 the means for effectingra: lockingitogether of the-upper front reachban -tube and a branch'of the center mass cluster- 12 assembly-is shown: Thisfmechanism"comprises nibbingpunches 388 38 I the tool 380 being effective during assembly-0f the-boys type frame; while the tool cams effective'during assembly of the girls type 'framei I? These tools-are disposed to extend'through openings formed in the guide blocks 26!] and 3iit and are blunt pointed to nib 'i or distort and indent a portion of the wall of a branch of the clusteivinto thewall oi the end of i the fro'nt reach bar *tube in both the boys and girls type of framea 'The tools 38!l-3Bi maybe 1 carried bya slide member- 383 and the'slide mem-" ber-efls eomprises a built-up structure operable I in slideway members' 385386;' supported by a spacer plate 381 which rests upon the machine bed plate Hill Disposedbetween the slidewayx members 685-386 is a compression spring are disposed to react against 'a lug 383a depending from 'the slide383; the "other end of the spring" abutting 'theslideway 386. -'Ihespring serves to shift'theslide andthenibbing-tools carried thereby away from the-frame clusters The slide 383 is operatedin a worlc performing: direction by a cam-3Sflfheld in positionrel'ative to'the slide structure =-by an L-shaped slideWay-member 39!, which is secured to the-spacer blo'ckSE'l on opposite sides of the-'slidway structureior the slide eXtend-ing toward, and secured-to, the slide smwhich carries -t-herear forkclamping mechanisms: A bracket -392-on-the slide member '3! affords rigid connection between slide '3) and cam-$9M} It vi11 t)e seen that thenibhing orlockihgaction of the tools-888 38! will be effectedduring the'lat'ter part of theforward move ment of theslide 3-! Bjthe irontedges-of the frame" having been moved' partia'lly into press fitting engagement withthe 'center mast cluster structures-and hanger-housing prior to the completion of this last mentioned operation.

In 'Figs. 26 and 27a source of hydraulic power for operating the-various systems hereinbefore referred' to "is generally shown as comprising a hydraulic 'pump and fluid reservoir mechanism,

indicatedbythe reference numeral 4%, the pump being driven bya motor diii'i- A yalving mechanism, generally indicated bythe reference numral 432,- is operatedbythecontroller:mechanism generally indicated bythe reference numeral Q03, positioned: on 'theqtop of the machine bed lit,

there being-controllerrods 40% extending downwardly to the valve mechanisms iifl whereby hydraulic pressure may be transmitted from the pump to hydraulic cylinder H4 and cylinder 3&6 in the sequence named and'i-n sequential relation Withthe-various manual operations hereinbeiore described; There are two controller rods, each one operating a reversible valve mechanism so that hydraulic pressure may be used to operate thepiston-cylinder mechanisms I74 and 348 in both directions.

In Fig."26'a second hydraulic unit 4:25! is in dicatedas being -driven'bya second motor Mi,

there being the valving mechanism M2 controlled in 'the"*mannerhei'einbefore"*described with reference to valving mechanism 403. This hydraulic unit may be connected'to piston-cylinder mechanisms l H, I12 and 225 for operating the front head' and hanger housing tube gauging and show-n) The "mechanism for-stripping the assembled frame from thdmachihahd the various clamplng and" gauging fixtures "thereof comprises a clamping mechanisms in anobvious manner (not I pisto'n cylinder mechanism420 '('see"Figs.- 28 and 29), supported by a beam member 42I, which beam member is secured to hollow columns 422- 423. These columns rest upon and are secured to a cross-structure 424 forming part of the machine frame. The piston rod of the piston-cylinder mechanism Mills connected to an elevatable plate structure 42%, upon which rest pin members located immediately beneath the hanger housing perimeter and the center .mast cluster structure positioned in the machine. The pins extend through the various clamping mechanisms acting upon these parts of the bicycle frame. For example, disposed immediately beneath the lower perimeter of the hanger housing tube are four pin members 435 equi-angularly spaced and of such lengths as to extend upwardly through the lower part of the hanger housing clamping mechanism to engage the lower edge or perimeter of the housing tube. A pin 43I is likewise provided to extend upwardly and terminate immediately beneath the cluster structure I65 of the girls type frame and pin 632 is similarly provided to extend upwardly and terminate just beneath the cluster structure I62 of the boys type frame. Thus, elevation of the plate 426 by the mechanism shown will serve to strip the completely assembled frame out of the various gauging blocks and fixtures comprising the machine, all of these fixtures being first conditioned of course to permit a free upward movement of the frame. This stripper mechanism may be operated hydraulically of pneumatically, as desired.

The operation of the machine is as follows. Clamping block It for clamping the head tube 49 is swung out of position by shifting its supporting lever II to a position 90 degrees from that shown in Fig. '7. The guide bar 2 II is shifted by manually operated lever 2I2 to its retracted position to the right in Fig. 1'2. The two head tube gauging plugs I89 and I99 are shifted to their outermost position by operation of the pneumatic piston-cylinder mechanisms. The hydraulic piston-cylinder mechanism li ter is shifted to the outermost position to the right in Figs. 3 and 10. The channel of the guide block 285 is opened by having its hinged closure member 286 swung to open position. The guide blocks 235--238 are open by having the hanger housing clamping slide 228 and the guide closure blocks 236-239 thereon in up position. Thus, the forepart of the machine is conditioned to receive a boys type sub-assem bly comprising the head tube 49 and the two forward reach bars 5253. The rear clamping mechanisms on slide 3", (Figs. 4 and 5) are in a retracted position to the left of Figs. 4 and 5. Gauging plugs i89- I9Ei are then pneumatically shifted toward each other to fit into the ends of the head tube 49, the inner configurations thereof being such as to act as spacing abutments for the head ends of the tubes 52-53. Clamping lever I l is then swung about its pivotal mounting to bring clamping block it over the head tube 49 whereupon camming lever I2 is manually shifted upwardly to cause its cams 3 to firmly compress clamping block It on the head tube 49. This clamp may be omitted when pre-assembly accuracy is available. The hinged guide closure member 286 is then swung to close the channel, in guide block 285 where it is secured in nonclamping relation to tube 52. The retractable member 2i I is then shifted over tube 52 to the position shown in full lines in Fig. 1'3. The forward sub-assembly of the frame is then conditioned to be acted upon by the hydraulic slide mechanism I'M-Ilsa. The center mast assembly 14 previously has been or now can be positioned in the gauging block 2I5. The clamping lever 262 (see Figs. 20 and 20A) is then operated as described to bring clamping block 26I upon center mast cluster member I62. I

The two rear sub-assemblies are then positioned with the rear axle plates I32 thereof on the contoured clamping blocks 3 I 83 I 9 with the forward free ends of the tubes I3BI3l disposed in the channels of the guide blocks 2I6 and 238. The levers 321 and 33I (see Fig. 5) are then swung clockwise to cause clamping blocks 32I and 32m to firmly clamp the rear axle plates I32 on the respective blocks 3I8 and 3I9. The channel of guiding block 260 may then be closed by the hinged closure member 215 (see Fig. 200 whereupon the spacer bar 282 is shifted inwardly to space the free ends of the two upper rear fork tubes relative to the rear branches of the cluster structure I62. The hanger housing is then gauged and clamped through lowering of the clamping slide 220 by pneumatic operation, and by this same action spacer bar 246 is shifted inwardly to space the free ends of the lower rear fork members I3I (note Fig. 23) relative to the radial apertures formed in the hanger housing tube I65. Lowering the slide likewise effects the closing of the channels of the guide blocks 235-238 as explained.

The head tube assembly is then shifted toward the apertures of the center mast cluster I62 and hanger housing I69 by hydraulic operation of slide I98 in the manner described, whereupon the channel guide blocks 235285 guide the tube into the said apertures in an accurate manner during this press fitting action. The curved tube 52 slides along the top surface of the fixed block 209 and the curvature thereof is followed by V the vertical surface 'of the member 255 by reason of the action of the slide operating member 2%, which is fixed to and shiftable with the crossslide structure carrying the head tube end of the front sub-assembly. The hydraulic press fitting of the ends of the tubes 52-53 to the cluster and hanger housing structure, respectively, continues until the ends of these tubes abut the cylindrical wall of the center mast tube and the gauging surfaces of the plugs 2I5-2I9 so that the general longitudinal over-all positions of the tubes 52-53 relative to the final frame assembly will always be substantially predetermined. The rear hydraulic mechanism 3| I is then operated to cause the clamp carrying slide 3 It to shift toward the center mast assembly position, thus causing the ends of the upper fork tubes I36 to be moved along the channel of guide bloc}: 2% while being subject to the spacing and guiding M influence of the spacing and guiding bar 282. In like manner the lower tube ends I3I are guided into the channel block 238, subject to the spacing and guiding influence of slide bar 240 so that the ends of these respective pairs of bars or tubes are accurately presented to the apertures of the branches of the cluster I52 and to the apertures formed in the hanger housing tube Ifiii. Continued operation of the slide 3H3 advances the tube ends until the ends of the lower tubes I3i encounter the gauging blocks 2 i 5-2 i 9 in the hanger housing and resistance to the hydraulic pressure stops operation of this mechanism. In the meantime thestabilizing shoes 355-356 are caused to follow the movement of the respective pairs of 75 bars to stabilize these bars and prevent lateral pression forces by 'ziction of hydre'uliC-Eylihder rection operates cam membef flfli to oause-the indenting tool 383 150 forri'i"em indentation in the indels H4 and 346 f the" Various Clamping and gauging mechanismsare the'n opened "the ba- 282 24fi and 2-!l"-zi-re retrel'cted j and the 'p'numatic e1anipingmeehahisins for the heeid tube tube c'iuster an.d"* the' two pairs of small wear fork tubes and rear axle plzrtes, supporting the 'seeo'ndf na'nie'd 'sub-"ass'er'ribiy;' "movabiy" supporting the other sub essernibiiesf and I f orcingj the free ends of thesmali 't'u of the'other sub-assemblies into openings formed in the-"center 'mest tube cluster and the hangerhousing tube While gaugingthe' opposite"fore-assembled"ends f the small tubes" and -during which intermediate portions of someof the movably Suppo'rteci' tubes'aresubjected' to T a traveling tra'nsverseaction coincide-Ii meme movement o'f the tubes whereby the final assembly of the" various frame --'e1ements are prelhn'i naril'y and s'ufiiientlyfastenedtogether"at the i and-.ha'ngerhwsmg tubeT eith n' hiftd*t gp n'ilfi vavrious joihts bf the fragm'ej strueture to remain" position? The rear hydrauueeyimdermechamsm 5 a e bl fl l t lmf a Fib??? l' 340 is thenrevers'ed' by bperation o'f the' controIs PFQP et e e dme n eee mer t. f to retract-the 'sii'de am; The completely-'fi'ssembled went to slmulta'neous copper'brazmgof fraimeis now conditioned for removal.

The stripping 'mechmni's'm, comprising the plate 42$a3 nd pins 430, I3 Fahd-432,35 the'n'operated by th pistori oylihdr' me'b hamsm 420 to 1 lift 'the Ir plate 426; thus causing' theupper'ends of the -pins to act upon the low'eflfierirri'eter of' 'th'e hah'g housin'g tube'and-the under 'sid'bf the writer: nia 's cluster structure to elevate-the entire frame move the head tube end of the amefre" of the cross-slide structure. The ems slide struoture ,j may thenberet'reicted byhydrau-I- perajtion of the' same and. th me'hanislfi is tfor "thereceptio of 'aEnotherfreime assembljnrr The foregoirf operationis described "With ref eren'ce to 'aboys'typebidycl'e'fratmel The opera bores formed in thefiargeWubewvaHs which enm2- prises effecting four pre assembliesconsisting of large'hezcd tube ands'mall'er front reach bartubes;- at large hanger "housing tubeend a' smallercenter mast'tube with "a centermast tube cluster and the two pairs of=sma11 rear:fork tubes -ayndrear'exle' plates, rigidly supporting-=-the second named sub-'assembly-a-nd movably supporting-the:

othersub-assemblies-while=foroing the free ends of the tubes- 0f the other sub-assemblies we into openings formed in the center-masttube cluster the hanger housing tube, -respectively,- andwhile simultaneously supporting'each fork tube the frame joints.-

3. The method of mahufa'cturirig'bicydieframes formed or large andsmail diameter tubul'a'r- 'elements'having' the endsther'eof press-fitted into boresforme'd'in the'lar'ge tube walls which com I prises 'efieoting four Dre-"assemblies oor'isisti'rig of th heed tube and f'ro'r'it' reach: bars 'and the" han'ger housing and-center tube "anda ceritermast 'tube 'cluster; the two pairsof rear forks and rear eJXTe" plates," rigidly supp rting theses ondn'aine'ii sub-assembly;'"movbiy' supporting the of the tubes of the-other sub-assemblies into open ingsfbllfi'ed in the center 'z'nast tube cluster and the'hanger housing;- tube'wh-ile gauging the 'opposite 'pre-assembled'ends of the small tubes and" t t o 50'while lsimultaneousl S11 per-tie" e'aohforktube tion is the s'ame for a girl's" type frame with the J g p g exception"- that v the additiohaf blam'ping' means i during its movement bye, traveling transverse action-u on the fork tubes" intermediate the ehds thereoffand effeotifi'g a look betwe'e'r'i' the mast tube'bluster and an uppertubewhil'e' maintain ing said foroed'alctiohs upon the tube elements and after thegauging actions have been" cornplete'd.

4. The method of manufa'oturingbieycle frames boresformed'in 'the large tube walis whioh com: prises effecting pre assemblies' consistingof the hea' d tube and front'rezich bars thehan'g'er nous cluster, the'two pairs of rear forks and'rear axle" plates, placing the respective pre-assembhes in reia'tive "position rigidiysupportihg the" second namedsub-assembl jjsimultaneously forcing the' free "ends of the tubes of the other twosub assemblies into openings' form'ed in the"enter" ms't' tube clujsterend' the hanger housing by simultaneously shifting the fork assemblies and the'headessemblfy toward the mast tube assembly' and iocking' one "of the front reach i'a'aftuiaes during its movement bya traveling transverseim t m a mast clusteh action upon the fork tubes intermediate the'end's thereof to thereby efiect afinalpressfitt'eii ass'em bly which will withstand expansionana contrajc tion of the frame elementsdurin'g ei'simultaneous' 5. The'methodof manufacturing-bic cle fra'm'e's' formed of large and small diameter tubularelemerits having the ends thereofriress' fitted '"into 1 bores formed in the'large'tubewelis which comcopper brazing operation" Whereinithe entire'f' fifi prises effe'ting'fourpre asSembIies'c'onsisting of frame is subjected to temperatures of "from 2000' to 2080 F 2. The method of manufacturing bicycle frames formed of large'and. small diameter tubular ele a large'head "tube and front reach 'bar'tubes'bf smalief'diametete large hanger housing tube and'sma lier' center mast tube a'ndfa' center "ms/st tube cluster; two pairs of smell rear fork tubes ments having" theends thereof "press fitted into '70 and rearraxle*piates," rigidiy su porting the's 'g; bores formed in the large tubewei' ls whic'hf com prises efieeting four'pre-eissemblies"consisting 'o'f ondnamed sub-assembly, motabiy supporting the 1 other sub-assemblies substantiaily aiigning" the freeends of "the tubes-of the other sub a'sserriblis with 'operiings of lesserfliameter of the renter mast-assembly, end for'cing' thTree 

